1. Field of the Invention
The invention relates to filter assemblies and to methods of making filter assemblies.
2. Description of the Prior Art
Filter assembles comprising a pleated filter media in a housing are well known. In annular shaped filters the filter media is in a closed loop and is bonded between outer and inner plastic sleeves. Known methods for making this shape of filer are not satisfactory because of the difficulty in bonding the sleeves to the filter media. Problems include difficulty in applying adhesive to the entire contact surface, excess adhesive being spread over the filter media and poor bond quality resulting in leakages such that dust could pass through the leaks instead of being blocked by the filter.